(absolving him of the foot rules but not the glide clear)
Not completely correct.
In UK, a SVFR clearance does absolve the pilot from compliance with the "1,000 foot" rule, but even then, the "500 foot" rule still applies for any flight over a congested area, irrespective of an ATC clearance to the contrary.
The only exemptions are if the pilot is taking off or landing at a government or licensed airfield, or under the terms of a specific written permission from the CAA. This applies to single and twin engined aircraft, including helicopters, btw.
In my office I have a box file full of written permissions, now at a mere £113 a pop from the CAA.